John Allen was the
instructor supervisor of the computer maintenance officer school and had
field maintenance experience in Michigan and Virginia:The AN/FSQ-7 was maintained for many years by a
staff of IBM technicians. In 196x the U S Air Force started to train
military technicians to maintain this system. It normally was operated in
the mode of one systed providing for the air defense mission and the
second unit being used to provide data processing, providing for the
programming and program debugging, and on second shift being maintained.
There were no technicians running around replacing tubes. The maintenance
was done by operating maintenance programs which stressed the operating
envelope of the vairious components and thereby prediced failures. A
plug-in unit was then replaced and sent to a lab on the premises for
analysis and if necessary repair.

Another responsible for maintenance on the Q7
disagrees with a paragraph of the summary:
The third paragraph says there were "several hudred tube failures
each day, replaced by workers racing up and down the tube racks with
shopping carts full of replacements."
This is NOT at all true. I was in the Air Force and did maintenance
on a Q-7 and it was NOTHING like that. It was normally scheduled
maintenance and we removed and replaced the pluggable units. It was
actually rare for the computer running the active program to fail.

About the built-in speaker, Doug
Elliott specifies:There was a volume controled speaker on
the main maintenance panel, extreme upper left. This was the only
place sound was heard. We would program Christmas music for it.
The reason the speaker was used was to monitor data being processed.
I don't know where the signal tied into but we so got used to hearing the
pink noise laced with changing tones of boops and beeps that we didn't
hear it. But when the sound just stopped, we noticed it. That's when the
computer would freeze with no alarm. So we just hurried and swicthed
over to the other one. Kinda exciting when they both went down.